Abstract
Meyer and Fischer b][MF] proved that nondeterministic finite automata (NFA) can be exponentially more concise than deterministic finite automata (DFA) in their representations of regular languages. Several variants of that basic finite state machine model are now being used to analyze parallelism and to build real-time software systems [HL+]. Even though these variants can sometimes represent regular languages in a more concise manner than NFA, the underlying models fundamentally differ from NFA in how they operate. Degree automata [W] (DA), however, differ from NFA only in their acceptance criteria and accept only regular languages. We show here that DA are also exponentially more concise than NFA on some sequences of regular languages. We also show that the conciseness of probabilistic automata [R] with isolated cutpoints can be unbounded over DA and, concurrently, i.e., over the same sequence of languages, those DA can be exponentially more concise than NFA.
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F. M. Ablyv. The complexity properties of probabilistic automata with isolated cutpoints.Theoretical Computer Science, 57:87–95, December 1988.
D. Drusinsky and D. Harel. On the power of bounded concurrency, i: The finite automata level. Technical Report CS89-20, Department of Computer Science, The Weizmann Institute of Science, Rehovot, September 1989.
J. Hartmanis. On Gödel speed-up and succinctness of language representations.Theoretical Computer Science, 26:335–342, 1983.
D. Harel, H. Lachover, A. Naamad, A. Pnueli, M. Politi, R. Sherman, A. Shtull-Trauring, and M. Trakhtenbrot. Stalemate: A working environment for the development of complex reactive systems.IEEE Transactions on Software Engineering, 16(4):403–414, April 1990.
D. Kozen. On parallelism in Turing machines.Proceedings of the 17th IEEE Symposium on Foundations of Computer Science, pages 89–97, October 1976.
C. M. R. Kintala and D. Wotschke. Amounts of nondeterminism in finite automata.Acta Informatica, 13:199–204, 1980.
C. M. R. Kintala and D. Wotschke. Concurrent conciseness of degree, probabilistic, nondeterministic, and deterministic finite automata.Proceedings of the 3rd Symposium on Theoretical Aspects of Computer Science, pages 291–305, January 1986.
E. Leiss. Succinct representation of regular languages by boolean automata.Theoretical Computer Science, 13:323–330, 1981.
E. Leiss. Succinct representation of regular languages by boolean automata, ii.Theoretical Computer Science, 38:133–136, 1985.
A. R. Meyer and M. J. Fischer. Economy of description by automata, grammars, and formal systems. InProceedings of Symposium on Switching and Automata Theory, pages 188–191, 1971.
A. Paz.Introduction to Probabilistic Automata. Academic Press, Reading, MA, 1971.
K. Y. Pun. Descriptive conciseness of degree automata. Master's theis, Pennsylvania State University, University Park, PA, 1986.
M. O. Rabin. Probabilistic automata. In E. F. Moore, editor,Sequential Machines. Addison-Wesley, Reading, MA, 1964. Also appeared inInformation and Control, 6(3):230–245, 1963.
B. Ravikumar and O. H. Ibarra. Relating the type of ambiguity of finite automata to the succinctness of their representations.SIAM Journal on Computing, 18(6): 1263–1282, December 1989.
R. E. Stearns and H. B. Hunt, III. On the equivalence and containment problems for unambiguous regular expressions, regular grammars and finite automata.SIAM Journal on Computing, 14(3):598–611, August 1985.
D. Wotschke. Degree languages: A new concept of acceptance.Journal of Computer and System Sciences, 14(2): 187–199, 1977.
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Detlef Wotschke was supported in part by “Deutsche Forschungsgemeinschaft” under Grant No. Wo 334/2-1 and by “Stiftung Volkswagenwerk” under Grant No. II/62 325.
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Kintala, C.M.R., Pun, K.Y. & Wotschke, D. Concise representations of regular languages by degree and probabilistic finite automata. Math. Systems Theory 26, 379–395 (1993). https://doi.org/10.1007/BF01189856
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DOI: https://doi.org/10.1007/BF01189856